1. Technical Field
Various embodiments relate generally to a semiconductor device and a method of manufacturing the same and, more particularly, to a three-dimensional semiconductor device and a method of manufacturing the same.
2. Related Art
A non-volatile memory retains data stored therein even when not powered. Two-dimensional memory devices in which memory cells are fabricated in a single layer over a silicon substrate have reached physical limits and may no longer have increased degrees of integration. Accordingly, three-dimensional (3D) non-volatile memory devices in which memory cells are stacked in a vertical direction over a silicon substrate have been proposed.
A 3D non-volatile memory device includes interlayer insulating layers and word lines stacked alternately with each other and channel layers penetrating therethrough. Memory cells are stacked along the channel layers. In order to selectively drive particular memory cells, a pad portion is to be formed on each word line, and a contact plug is to be coupled to the pad portion.
It is difficult to form pad portions on word lines stacked on top of one another and form contact plugs so that the contact plugs are coupled to the pad portions. In addition, a punch phenomenon may occur in which a contact plug passes through a pad portion, or the contact plug and the pad portion are not coupled to each other since a pad portion is not exposed along a bottom surface of a contact hole.